Make sure HTC Sync Manager is not installed at all if you want Android File Transfer to work. This has been an issue in the past, although it doesn't sound like the issue here though. I personally don't have a problem using HTC Sync Manager to transfer my files, but if course I can see why people wouldn't want to use it.
I think the reason MTP is such crap on Macs is that Microsoft owns the license for the MTP protocol, and they let everyone use it except Apple, thus making Windows a more appealing OS. Just a theory though...
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Samsung Galaxy Note 8.0 N5110 Stock 4.2.2 rooted
Rogers HTC One
HP Touchpad with CM10